Skin temperature distributions over veins and tumours

The metabolic heat production per unit mass of tumour is first estimated from published values of the metabolic quotients for various tissues. The calculated thermal patterns at the skin surface due to heat conduction from tumours or veins at various depths are then presented in charts. These permit estimates to be made of the maximum depth at which veins or tumours of given size would still produce detectable increases in skin temperature. It is shown that tumours less than 0.8 cm in diameter could hardly be detected by their metabolic heat. The observed thermal patterns over malignant tumours of small size are evidently due chiefly to some effect of the tumour on the blood flow in the superficial veins.